Should you build your own Skribbl?
Infinite canvas where coding agents run as live terminal nodes you wire together by drawing
The canvas is the easy half. React Flow plus xterm.js plus node-pty gets you panning, zooming and half a dozen live agent terminals in a weekend, and it is a genuinely nice way to watch a fleet work. The gaps are all in the boring layer underneath: knowing when an agent is actually blocked on you rather than just quiet, keeping sessions alive across a restart or a crash, and counting tokens accurately enough that the number can be trusted. Each of those is days of work on its own, and the weekend build reads as finished until the first agent silently dies behind a tab you were not looking at.
ENOriginal research content in English. Original prompt preserved in English.
Build me a canvas for running several coding agents at once, like Skribbl. Requirements:
- Electron plus React, with React Flow for the pan/zoom canvas and xterm.js plus
node-pty for the terminals. No web version, this is a desktop app.
- Each node is a real shell in its own process, spawned with node-pty in a working
directory I pick per node. Double click empty canvas to add one, and let me type in
it exactly like a normal terminal.
- Node position, size, title and cwd persist to a JSON file in the Electron userData
folder, restored on launch. The shells themselves do not survive, say so in the UI
rather than pretending they do.
- Spawn each shell inside `tmux new-session -A -s <nodeId>` so a crashed window can
reattach to the running agent instead of killing it. Budget real time for this, the
reattach and scrollback restore is the fiddly part of the whole build.
- Drag from one node to another to draw a link, and store the links with a direction.
Right click a link to delete it. Links are just recorded relationships for now, no
message passing between agents.
- A top bar counting tokens per node, parsed from each agent CLI's own usage output.
Keep input, output, cache write and cache read as four separate counters, never sum
them into one number, a cache read costs about a tenth of an input token.
- Out of scope: multiplayer, cloud sync, code signing, and any status indicator you
would have to infer by scraping terminal output. Guessing wrong there is worse than
showing nothing.
- README with the node-pty rebuild step for your Electron version, which is the one
thing that will break on a fresh machine.The prompt opens pre-filled in your agent. Review it before running.
What would building your own look like?
Spawn real shells as draggable nodes on a pan/zoom canvas, run a coding agent in each one, and watch several of them work side by side.
What you will need
- Node 20 and native build tools for node-pty
- A coding agent CLI already installed and authenticated
- tmux, if you want sessions to survive a restart
Not for the canvas. For the layer that keeps twelve child processes honest: status that comes from the agent itself instead of scraped output, sessions that come back after a reboot, and a spend number accurate enough to act on before the bill arrives.
xhook-driven agent status, so a blocked agent looks the same as an idle one
xsession survival across restarts and crashes
xan accurate token meter, cache reads price nothing like input tokens
xa signed and notarized Mac build, so Gatekeeper blocks what you ship to anyone else
How much does Skribbl cost?
- Monthly billing
- $49/mo$49/mo
- Per year
- $588/yr$588/yr
- On a Brazilian card, with 3.5% IOF
- R$256/moR$3,073/yr
Saved to My list. You will see a notice on this site when the price changes.
You complete the purchase on Skribbl’s site. Vibe Radar does not handle payments.
| Plan | Monthly | Annual (per month) | What is included |
|---|---|---|---|
| founding infinity | $29/user≈ $29 | $8.25/user≈ $8.25 | 3 concurrent agents; founding-plan access while licenses remain available. |
Free tierno free tier; 14-day trial only
Billing termsmonthly or annual
Additional costsThe plan does not include Claude Code, model API or other agent-provider subscriptions; the trial requires a card from day 2 and charges on day 15 unless cancelled.
verified 2026-08-14 · source ↗
Is it cheaper to build or buy Skribbl?
Adjust the numbers: hours to build, your hourly rate, running costs and the subscription price.
Over 24 months, subscribing is cheaper.
Starting hours estimated from the analysis (a weekend for the canvas, multi-day for the parts that make it trustworthy). Does not price what you give up (support, integrations, security).
Can I rebuild Skribbl?
Kinda. The core of Skribbl is buildable in a weekend with the prompt on this page, but there are real gaps: hook-driven agent status, so a blocked agent looks the same as an idle one, session survival across restarts and crashes. Read the honest list above before committing.
How much does Skribbl cost?
Skribbl costs about $49/mo (wayari, checked 10/20/2026), which is $588 per year.
What do I lose by replacing Skribbl?
Honestly: hook-driven agent status, so a blocked agent looks the same as an idle one; session survival across restarts and crashes; an accurate token meter, cache reads price nothing like input tokens; a signed and notarized Mac build, so Gatekeeper blocks what you ship to anyone else. If any of those are load-bearing for you, keep paying.
Is there an open-source alternative to Skribbl?
Yes: claude-squad (open-source terminal manager for multiple agents in tmux and git worktrees), Crystal (open-source desktop app running parallel agent sessions in worktrees), vibe-kanban (open-source board for queueing and reviewing coding agent tasks). Using prior art is also vibecoding; the prompt is for when you want it exactly your way.